Depth mode characteristics of light propagation in real turbid media and media with two-dimensional scattering

Light propagation in a two-dimensional medium with large inhomogeneities

“…As is known, the quantum-mechanical eigenvalue problem for the "potential" (15) has an analytic solution [35]. The eigenfunctions of Eq.…”

“…The factorization of the intensity into the zand θ-dependent terms corresponds to the asymptotic regime of multiple scattering. In this regime, the angular distribution (normalized to unity) of light no longer varies with the depth [12,15].…”

“…(15)], the eigenfunctions Φ n ω and Φ v ω have definite parity (or, more precisely, for the continuous spectrum such eigenfunctions can be constructed). In the case of normal incidence, the intensityĨz; θ and its Fourier transformĨ z; ω are even functions of the variables θ and ω, respectively, and the odd eigenfunctions make no contribution to the expansion (16) [12,16] and c 2m1 0, where the parameter s is defined by Eq.…”

“…Of particular interest is the multiple light scattering in various lowdimensional disordered systems [8][9][10][11][12][13][14][15][16][17][18][19], including artificial two-dimensional media [20], nematic liquid crystals [21], and biological tissues [7,22].…”

“…If the medium depth is less than the transport mean free path, multiple scattering of light is predominantly small-angle [3,4]. In absorbing media where the absorption coefficient is greater than the transport scattering coefficient, κ > σ tr , isotropization of the beam does not occur at all (because of absorption of light propagating along strongly curved trajectories), and small-angle multiple scattering predominates at any depth (e.g., [15]). In this case, spatial and angular distributions of scattered light can be described by a solution to the radiative transfer equation in the small-angle approximation [3,4].…”